Tagged Questions

Why is the Poynting Vector symmetric in E and H? I always thought that E and B were the analogous fields, so I would think that any equation using magnetic and electric fields should be symmetric in ...

I am able to prove in a few lines that the electrodynamic field vectors $\vec{E}$, $\vec{H}$ and $\vec{S}$ are all orthogonal to each other considering that $\vec{E}$ and $\vec{H}$ are coherent plane ...

To calculate the elastically scattered intensity of x-rays from crystals, one classically considers scattering from a free electron first and then one sums up the scattered em-fields of all electrons ...

How does one show the momentum imparted to a perfect conducting resonance cavity (boundary) of any shape by a classical standing electromagnetic wave inside is zero?
It should be by conservation of ...

Electromagnetic momentum density and the Poynting vector are related by the simple expression:
$$ \textbf{g} = \frac {\mathbf{S}}{c^2}$$
It can be rigorously derived from Maxwell's equations, but is ...

I'm looking for a physical interpretation of the Poynting Vector. I understand that it should be thought of as an energy flow due to the electromagnetic field, but would I be correct in saying that in ...

The intensity of light (as calculated from time average of the poynting vector) is given by $I = (1/2) \epsilon v E_0^2$. Here the intensity is dependent on the velocity of light in the medium. The ...

How do you calculate the Poynting vector for a laser given it's power? I know for a sphere you can just take the power, and divide it by 4$\pi R^2$, but I don't know what I would do for a laser. Would ...

Given an electromagnetic wave in resonance mode in a vacuum cavity inside a perfect conductor, on the boundary, the parallel component of $E$ field vanishes, and the perpendicular of component of $B$ ...

I am using constant density wave propagators to model seismic waves in the subsurface. What I want with these acoustic waves is to estimate the energy of them at a certain grid point at a given time. ...

Take a plane wave propagating in the $\hat{z}$ direction in a non-magnetic linear dielectric. The real electric field is then given by
$$\vec{E}(r,t) = E_0\, e^{-k_i z}\cos(k_R - \omega t)\, \hat{x} ...

I am trying to derive the Poynting theorem. So far, I've only been able to narrow down which equations I think I'll need to do so. These are the equations:
Maxwell's Equations:
$$
\nabla\times{\bf E} ...

Below is an example problem that I know how to solve, particularly when the current is switched off and the magnetic field is allowed to decay.
However, in systems typically like these, is it a far ...